In situ molded thermal barriers

ABSTRACT

The invention provides methods, systems, and devices for installing barriers in openings or gaps in or between structures such as walls, ceilings, and floors. At least one barrier molding bag is positioned in the hole or gap, and a flowable firestop material that is preferably operative to cure or harden, such as a hydratable cementitious slurry, is introduced into the bag to create a barrier in the hole or gap.

FIELD OF THE INVENTION

[0001] The present invention relates to building structures, and moreparticularly to moldable thermal barriers for “head-of-wall” jointassemblies between top of walls and ceilings, “perimeter” joints betweenfloors and vertical walls, and other joints, gaps, or holes in buildingstructures.

BACKGROUND OF THE INVENTION

[0002] Firestops are thermal barrier materials or combinations ofmaterials used for filling gaps and openings such as in the jointsbetween fire-rated walls and/or floors of buildings. For example,firestops can be used in walls or floors to prevent fire and smoke frompassing through the gaps or openings required for cables, pipes, ducts,or other conduits. Firestops are also used to fill joint gaps that occurbetween walls, between a ceiling and the top of a wall (“head-of-wall”joints), and between a floor and vertical wall (“perimeter” joints).

[0003] So-called “head-of-wall” joints pose a number of challenges forthe fireproofing industry. Walls are increasingly being made of gypsumwallboard affixed to a framework of metal studs capped by a horizontallyextending track. Ceilings are increasingly being made by pouringconcrete onto fluted steel. Although the distance between thehorizontally extending track at the top of the wall is often fixed inrelationship to the ceiling, the gypsum wallboards are subject toexpansion and contraction due to motion of other building components,ground settling, or other causes.

[0004] For such head-of-wall joints, it is known to use mineral woolbatt as a thermal resistant firestop material due to its ability toprovide for cyclic movements in the wallboard material. The mineral woolis cut into separate sheets that are appropriately sized depending onthe specific geometry of the fluted steel ceiling. The sheets need to bestacked and compressed (e.g., a minimum 50%) when packed into the jointgap. In some situations, a fireproofing material is spray-applied intothe spaces of the fluted ceiling to supplement the mineral wool in thejoint. In either case, the mineral wool approach requires labor andtime.

[0005] After packing of the mineral wool batt into place above the wall,the construction worker must then spray an elastomeric coating, using aminimum one-eighth inch thickness, against the exposed side surfaces ofthe compressed mineral wool layers. The coating must overlap a minimumof one half inch onto the ceiling and wall surfaces. Thus, the use ofmineral wool batt and elastomeric spray coating provides for the abilityof the resultant firestop to accommodate some cyclic movement(compression and extension) in various components such as the gypsumwallboards on either side of the head-of-wall joint.

[0006] So-called “perimeter barrier” systems also typically employmineral wool and elastomeric coating as firestopping material in thejoint gaps between floors and the surface of a wall, which could be aninterior partition or an external wall. In this case, the mineral woolbatt must be packed tightly in the gap, to improve its fire resistance,and so that upon expansion of the gap due to shrinkage of the floor ormovement of the wall, the mineral wool does not fall out of the gap andinto the floor level below. An elastomeric spray coating is then appliedonto the top face of the packed mineral wool batt, but in most cases thebottom of the mineral wool batt is not coated. This is often due to thefact that the wool batt must be accessed from below, requiring thatladders and spray equipment be moved downstairs and set up.

[0007] One objective of the present invention is to provide a moreconvenient and cost-effective method for installing a thermal barrier inintricately shaped openings and joint gaps such as are found in“head-of-wall” joints, “perimeter” joints, and other variously sizedand/or intricately shaped gaps or openings such as penetrations throughwalls. For example, openings having plastic pipes or plastic-coatedwires often require an intumescent firestopping material for sealing thespace left by the plastic material after it has melted in the fire.Sometimes an intumescent caulk material is inserted into suchpenetration openings. In the case of larger diameter pipes, a metalcollar is used to retain the caulk in place. In other cases, wrapped orbagged mineral wool with an intumscent material is inserted into thehole. In any case, installation of such firestopping is time-consumingand expensive.

[0008] Another objective of the invention is to provide novel thermalbarriers that may be used conveniently and safely in hard-to-reachbuilding or ship vessel joint gaps or holes. For example, the locationof a head-of-wall joint next to an elevator shaft or crawl space wouldrender difficult the installation of mineral wool/coating systems,because the task of coating both sides would be complicated by the lackof convenient access.

[0009] A still further objective of the invention is to enhance safetyof installation. An applicator must climb up and down ladders on afrequent basis when working on head-of-wall joint assemblies. In thefirst instance, there is the fitting and hand-packing of mineral woolmaterial into the joint gap. In the second instance, there is thecoating of elastomeric material to create a continuous surface betweenthe ceiling, firestop, and wall. In both cases, the ladder may requirefrequent repositioning, and this is especially the case where joint gapsextend lengthy distances of ten to twenty feet or more. Frequentclimbing up and down ladders would also be required in “perimeterbarrier” systems if it were desired to apply an elastomeric coating ontothe bottom face of a mineral wool firestop that has been packed betweena floor and a wall, because the installer would need to go to the floorbelow the firestop to coat the bottom face of the mineral wool material.

[0010] In view of the prior art disadvantages, novel thermal barriersand methods are believed to be needed.

SUMMARY OF THE INVENTION

[0011] In surmounting the disadvantages of the prior art, the presentinvention provides a method and system for installing a thermal barrierin openings and gaps in or between building structures such as walls,ceilings, and floors. In so doing, the present invention providesincreased convenience, effectiveness, and safety in comparison to theprior art mineral wool/coating methods. The thermal barriers of thepresent invention have the ability to conform intimately with the shapeof openings and gap spaces of various sizes and shapes. The thermalbarriers also have the ability to permit movement of the variousbuilding structures around the openings or gaps. In particular,protection on both sides of “head-of-wall” joint assemblies (arisingbetween a wall and ceiling) as well as upper and downward faces of“perimeter barrier” assemblies (arising between a floor and wall) may beconveniently accomplished by the thermal barriers and methods of thepresent invention.

[0012] An exemplary method of the present invention comprises providinga first structure (e.g., building or ship structure such as a floor,wall, or ceiling) having an opening (such as a hole for passage oraccess to cables, wires, pipes, ducts, electrical panels, etc.), orproviding first and second structures which define therebetween a gap(such as the joint gap between a wall and a ceiling or floor);introducing into the opening or gap at least one (empty) thermal barriermolding bag that is operative to receive and substantially to contain aflowable firestop material, one that is preferably operative to hardenwithin the bag; and introducing into the thermal barrier molding bag aflowable firestop material to expand the bag within the hold or jointgap, thereby creating a thermal barrier within the hole or gap.

[0013] Exemplary thermal barrier molding bags of the invention arepreferably made of thermoplastic film material (although other suitablematerials are hereinafter described) and preferably have at least two ormore openings, preferably of the type that can be opened and closed morethan once, that permit introduction into the bag of a flowable firestopmaterial, e.g., such as hydratable cementitious slurry, an intumescentmaterial, a superabsorbent polymer; polyurethane (foam); hydrated silicagel; inorganic dessicants (e.g., molecular sieves such as zeolites;silica gel; calcium oxide; calcium sulfate; calcium chloride; bariumoxide; phosphorous pentoxide); fibers; mineral wool; fiber glass; ormixture thereof. The molding bag material should be sufficiently sizedand shaped, and flexible enough to permit expansion of the molding bag,upon introduction of the flowable firestop material, and to permitmolding of a thermal barrier within at least a portion of the opening orjoint gap. Preferably, the bags are flexible enough to permit them to betransported in a compact rolled form (when empty) and unrolled intoplace in the opening or gap space (wherein they are expanded and filledwith the flowable firestop material).

[0014] Firestop barriers made in accordance with the above-describedin-situ methods of the present invention provide excellent fireresistance and sealing ability as well as smoke and acoustic barrierproperties. They are also sufficiently strong to resist dislodgementfrom the gap or opening due to pressure (e.g., force from a water hose)and are highly amenable to visual inspection.

[0015] Further features and advantages of the invention are described indetail hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following detailed description of exemplary embodiments maybe more readily appreciated in conjunction with appended drawings,wherein:

[0017]FIG. 1 is a diagram of a PRIOR ART “head-of-wall” joint assembly;

[0018]FIG. 2 is another perspective of FIG. 1 (PRIOR ART);

[0019]FIGS. 3 and 4 are diagrams of exemplary barriers of the invention;

[0020]FIG. 5 is a diagram of exemplary components of an exemplarybarrier molding bag of the invention having pleats;

[0021]FIG. 6 is a diagram of another exemplary barrier molding bag ofthe invention having inlets for introducing a flowable firestopmaterial;

[0022]FIG. 7 is a partial diagram of an exemplary inlet for introducingflowable firestop material into a molding bag of the invention;

[0023]FIG. 8 is a partial diagram of an exemplary tube or sleeve inletfor allowing flowable firestop material to be introduced into a moldingbag;

[0024]FIG. 9 is a diagram of an exemplary “head-of-wall” barrierassembly;

[0025]FIG. 10 is a diagram of another exemplary barrier of the inventioninstalled in a joint gap between wall and floor;

[0026]FIG. 11 is another exemplary barrier of the invention;

[0027] FIGS. 12-14 are other exemplary methods and barriers of theinvention;

[0028]FIGS. 15 and 16 are illustrations of a further exemplary moldingbag of the invention; and

[0029]FIG. 17 is a cross-sectional illustration of a further exemplarybag barrier assembly of the invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0030] The present invention employs one or more thermal barrier moldingbags that may be conveniently placed in openings in structure, such as awall, ceiling, or floor, or conveniently placed in gaps such as aredefined in the joints between walls, ceilings, and/or floors. Themolding bags are placed empty in the hole or gap, and a flowablefirestop material is introduced into the molding bag, thereby expandingthe bag to fill the space within the hole or gap, and the flowablefirestop material is then allowed to harden within the hold or gap toprovide a strong thermal barrier. The term “firestop” as used herein isintended generally to refer to materials that are intended to be fireretardant or fireproofing in nature, and a detailed list of exemplaryfirestop or fireproofing materials is provided in the followingparagraphs.

[0031] As shown in FIG. 1, a “head-of-wall” joint gap appears betweenthe top of a vertical wall and ceiling (PRIOR ART). In this drawing, thewall is made by attaching a horizontal metal track 12 or runner to afluted metal ceiling 10 which is shown running in a perpendicular mannerto the wall (12). The ceiling 10 has fluted portions 10B which aresomewhat lower than the top ceiling portion 10A, and thus a joint cavity16 is defined between the top ceiling portion 10A and the top of thewall, which in this case is the horizontal track 12. Metal studs 14 areattached to the horizontal track 12 and connected to the floor below. Asshown in FIG. 2, gypsum wallboards 18 are affixed on either side of thestuds 14 to complete the wall assembly (PRIOR ART), and gaps 20 aretypically left between the tops of the gypsum wallboard 18 andhorizontal track 12 to permit movement of the wallboards 18.

[0032] As shown in FIG. 3, an exemplary thermal barrier 1 of theinvention is made by placing or adhering an empty thermal barriermolding bag 30 on top of the horizontal track 12 before the track 12 isattached to or otherwise fixed into place against the ceiling surface10B. After vertical studs and gypsum boards are installed under thehorizontal track 12 to assemble a wall (which in this case is alignedperpendicularly with respect to the orientation of the fluted metalceiling 10), then flowable firestop material 32 can be introduced intothe molding bag 30 to fill the joint space 16 between the fluted metalceiling 10 and above the assembled wall 14 structure. Preferably, thethermal barrier molding bag 30 has a portion 33 thereof extending belowthe tops of the gypsum wallboards 18 on either side of the wall(12/14/18) to protect the exposed gap 20 next to the horizontal track12, so that heat and smoke do not penetrate through the wall at the topportion which is not covered by the gypsum wallboard 18.

[0033] Preferably, a spacer material (e.g., resiliently compressiblestrip of foam (STYROFOAM type), foamed rubber, expanded polystyrene,mineral wool, air balloon, etc.) is inserted at the corner gaps 20, toleave a space for cyclic movement of the wallboards 18 when the flowablefirestop material 32 is hardened.

[0034] As shown in FIG. 4, another exemplary thermal barrier 1 of theinvention can be made when the fluted metal ceiling 10 is oriented inthe same direction as the metal stud wall 14. In this case, a barriermolding bag 30 is positioned between the horizontal track member 12 andceiling surface 10B, with longitudinal edges of the bag (33) extendingoutwards on either side of the joint between the wall and ceiling,before the horizontal track member 12 is attached to (or otherwisedisposed against) the ceiling surface 10B. While no joint cavitytherefore appears on top of the wall in this case (because the spacesdefined between ceiling surfaces 10A and 10B appear on either side ofthe wall), the corner gaps 20 which are customarily left at the top ofthe gypsum wall board 18 nevertheless render the horizontal extendingtrack member 12 unprotected against fire. Therefore, a flowable firestopmaterial 32 is introduced into the molding bag 30, such that a thermalfirestop barrier is molded along the joint over the corner gaps 20 atthe top of the gypsum boards 18. Again, it is preferable that a spacermaterial (foam or mineral wool strip) be inserted into the gap spaces 20to permit movement of the boards 18.

[0035] Thus, an exemplary method of the invention comprises inserting athermal barrier molding bag 30 in the joint between two structures, suchas a wall and ceiling, and introducing a flowable firestop material intothe bag 30 so as to expand the bag 30 from an empty shape to a shapeconforming to the space between or around the two structures, andallowing the firestop material to harden inside the bag 30, whereby athermal barrier 1 is molded.

[0036] The thermal barriers of the invention are contemplated primarilyfor use in joint assemblies (e.g., floor-to-floor joint systems,wall-to-wall joint systems, floor-to-wall joint systems, andhead-of-wall joint systems) as well as in “penetration” holes (e.g.,passageways in which pipes, wires, cables, ducts, electrical panels,meters, and other conduits or devices, are situated).

[0037] As shown in FIGS. 3 and 4, the positioned molding bag 30 isfilled with a flowable firestop material 32 that is operative to hardenwithin the bag 30, such as a hydratable cementitious slurry. The moldingbag 30 or bags should allow the introduced flowable firestop material 32to fill the hole or gap space completely, thereby providing an effectivebarrier against passage by heat and smoke. Although FIGS. 3 and 4 depictan application for sealing a joint defined between and/or along twostructures, it will be understood that the -exemplary method and bagdevice can be used for filing or otherwise protecting variously sizedand shaped holes in one structure or the joint gaps between two or morestructures. Two or more bags 30 can be used in concert in large holes orjoint gaps, such as by overlapping ends of bags, stacking the bags, orabutting two or more bags in an end-to-end configuration.

[0038] Exemplary molding bags 30 of the invention may be fabricated asone piece “tubes” or sleeves that may be sealed or otherwise closed atthe ends to form a container. More preferably, the bags 30 are made byheat sealing, sewing, adhering, or welding two or more sheets or filmstogether. The films or sheets may be made of different materials. Forexample, plastic sheets having different moduli of elasticity (Young's)can be used. For example, a highly elastic polymer film can be used forthe purpose of allowing the bag to expand into the space of a hole orcavity.

[0039] As shown in FIG. 5, another exemplary thermal barrier molding bag30 of the invention can be made using two separate sheets or films 30Aand 30B. The exemplary sheet or film component designated as 30A, whichin this case is designed to facilitate expansion of the molding bag 30into the joint cavities (designated at 16 in FIGS. 1-3), comprises oneor more pleats 34 made by folding the material. The folded top sheet orfilm 30A is then seamed (such as by welding or sewing) to the bottomsheet or film 30B to obtain the molding bag 30. Preferably, the top film30A has one or more air evacuation holes 36 to permit air to evacuatethe bag 30 when flowable firestop material is introduced. An exemplarycloseable inlet 38 is illustrated in the top portion of FIG. 5, which isdesigned to permit the flowable firestop material to be introduced intothe bag when the bag is positioned in the hole or joint.

[0040] Alternatively, instead of “pleats” (as shown at 34 in FIG. 5)which are a series of substantially uniform folds that extend from onelongitudinal edge of the bag to the opposite edge, another exemplarymolding bag 30 of the invention can have crimps or crinkles to permitexpansion when the bag is filled. The terms “crimps” and “crinkles” areused herein to refer to folds which are substantially irregular in thatthey are randomly located but preferably aligned generally in onedirection. In a manner similar to the series of pleats shown at 34 inFIG. 5, crinkles or crimps may be aligned in a substantiallyperpendicular direction with respect to the length of the bag 30. Thus,when filled with a flowable firestop material, the exemplary molding bagcan expand to fill a “head-of-wall” joint cavity between the wall andfluted metal ceiling (as shown in FIG. 5). It is preferable for thecrimps or crinkles to extend from one edge of the bag to another opposededge, like the series of pleats 34 shown in FIG. 5), although this maynot be necessary depending upon the expansion capabilities of the bagdesired.

[0041] The size and number of pleats or crimps or crinkles per linealinch of bag length will of course depend on the height or volume of thehole or cavity that is desired to be filled, as well as the width and/orvolume of the bag itself. The larger the hole or joint cavity to befilled, the more pleats, crinkles, and/or crimps would be needed in thebag to permit expansion of the bag to fill the hole or joint cavity.

[0042] For a “head-of-wall” joint cavity, which is formed between a walland perpendicularly-oriented fluted metal ceiling (See e.g., FIG. 3),the upper sheet of a bag should have sufficiently sized and/or numberedpleats, crinkles, or crimps to permit the upper surface bag to expand orenlarge, when the bag is filled with firestop material, to 150-250% ofits original size.

[0043] In a further exemplary embodiment, the molding bags may usepleats, crinkles, or crimps which are attached to elastic strips, in afashion similar to plastic shower caps that have integral elastic bandsfor helping to retain a compact shape. For example, one or more elasticstrips or bands may be sewn, in a stretched mode, lengthwise to atwenty-foot sheet; when tension is released from the elastic strips orbands, the sheet will shorten in length from twenty feet to ten ortwelve feet (depending how much the elastic strip was stretched) wherebythe sheet will have pleats, folds, or crinkles which can then expandwhen the sheet is formed into the molding bag. Preferably, at least twoelastic strips are used lengthwise on the upper sheet 30A of the moldingbag in a generally parallel fashion with respect to the longitudinallyextending edges of the bag.

[0044] The function of the elastic is to maintain the molding bag as arelatively compact sheet-like structure, thereby facilitating thepositioning of the bag into a hole around a pipe or in a head-of-walljoint cavity (between the horizontal track and fluted metal ceiling),but the elastic material will to permit the pleats, folds, or crimps inthe bag material to expand into the hole or joint cavity when thefirestop material is pump-flowed into the bag.

[0045] As another example, an elastic strip or band can be situatedlengthwise perpendicular to the direction of the pleats and/or crimps orcross-wise aligned parallel with the direction of the pleats and/orcrimps.

[0046] It may be preferable to use a series of pleats rather thansmaller crimps or crinkles in plastic sheet materials because the pleatsmay allow for greater melt-seam strength along the peripheral edges ofthe bag, as shown in FIG. 5. However, crimps (or crinkles) may provideconsiderable benefits when used in bags made of paper or crepe paper,such as in the paper tape backing used for making masking tape. Suchpaper is typically impregnated in an elastomeric latex and crinkled (orcrimped) so that it is capable of stretching and conforming to non-flatsurfaces. Hence, it is believed that the latex-impregnated and crinkled(or creped) paper used for making masking tape can be used to makesheeting components for molding bags wherein a settable cementitiousslurry can be received under pressure, without substantial leakage, andexpand by at least 150% of its original length or width to conformwithin a hole or joint cavity.

[0047] In further exemplary embodiments, the bottom sheet or film 30B ofthe molding bag, as shown in FIG. 5, can be made of material having ahigher modulus of elasticity in comparison with the top sheet or film30A. One reason for using a stronger or more rigid material for thebottom film 30B is that doing so may be more suited for the purposes ofattaching one or more closeable inlets 38. Another reason is that thebottom face 30B may be sufficiently rigid to retain a fold or archaround the comer gaps 20 shown in FIGS. 2-4. In further exemplaryembodiments, a flashing material, such as a rigid plastic or metal sheetcan be adhered to the bottom face 30B when the bag 30 is installed ontop of the wall, with corners bent to coincide with the corner gaps 20,thereby to resist the weight of the bag 30 and firestop material 32.

[0048] As shown in FIG. 6, another exemplary thermal barrier molding bag30 of the invention has at least two inlets 38 for introducing flowablefirestop material into the bag 30 while the bag is situated in a hole orjoint. Preferably, the inlets 38 are disposed along both longitudinaledges of the bag 30 (on either top or bottom sheets or films), so thatwhen the bag is installed on top of a wall in a “head-of-wall” jointassembly, an installer can introduce a flowable firestop material intothe bag from either side of the wall.

[0049] Exemplary flowable firestop or fireproofing materials 32contemplated for use in the present invention are preferably of the typewhich are capable of being pumped into the bag 30 and preferablyoperative to cure or harden inside the bag. The terms “firestop” or“fireproof” may be used interchangeably herein to refer to materialswhich prevent or minimize the spreading of a fire. The term “flowable”as used herein means and includes both dry and liquid materials, andpreferably refers to materials that can be pumped under positivepressure through a hose. For example, dry flowable firestop materialscan include fibers, such as mineral wool fibers, expanded vermiculite,expanded perlite, shredded expanded polystyrene, clay granules orprills, and the like, optionally with a binder material, such as alatex, a cement and/or gypsum slurry. Exemplary liquid flowable firestopmaterials can include hydratable cementitious materials, as furtherexplained below, as well as synthetic polymers (e.g., polyurethane,polyvinyl chloride, polyvinylidene chloride) preferably containinginorganic fillers to reduce flammability (e.g., sand, clay).

[0050] The term “hydratable cementitious” material as used herein refersto material that comprises at least one cementitious binder that beginsto harden when mixed with water. Such a binder may be Portland cement,masonry cement, or mortar cement, gypsum, stucco, Plaster of Paris,aluminous cement, pozzolanic cement, magnesium oxychloride, magnesiumoxysulfate, calcium silicate-hemihydrate, as well as materials such aslimestone, hydrated lime, fly ash, blast furnace slag, and silica fume.The hydratable cementitious materials may in addition optionally includefine aggregates (e.g., sand), coarse aggregates (e.g., crushed stone,gravel, carbon flakes), or other fillers. Further exemplary cementitiousmaterials may optionally contain, in addition to the cementitiousbinder, an intumescent material as will be further describedhereinafter.

[0051] Preferred cementitious materials include pumpable cement and/orgypsum slurries of the kind now employed in the spray-appliedfireproofing industry. Portland cement slurries, optionally havinggypsum, are especially preferred. Other suitable fireproofingcompositions are disclosed in U.S. Pat. Nos. 4,699,822 of Shu; 4,751,024of Shu; 4,904,503 of Conroy, Hilton, Korenberg; 4,934,596 of Driscoll,Hilton; 5,352,490 of Hilton, Korenberg; 5,340,612 and 5,401,538 ofPerito; 5,556,576 of Berneburg, Freitas, Pisaturo; and 6,162,288 ofKindt, Hilton, Perito. Such cementitious slurries are pumpable, becausethey are typically used in conventional spray applications, and wouldpermit the thermal barrier molding bags 30 to be filled rapidly. Whilesuch formulations may involve the use of fibers, aggregates, andfillers, these would be rendered optional in the present inventionbecause the molding bag 30 would serve primarily as the means formaintaining the integrity and shape of the cementitious slurry until ithardens.

[0052] Exemplary hydratable cementitious materials used as flowablefirestop materials 32 in the present invention may further include oneor more admixtures or additives, such as set accelerators, setretarders, water reducers (including superplasticizers and fluidityenhancing agents), rheology modifiers, air entraining agents, pigmentsor colorants, porous aggregates (e.g., shredded expanded polystyrene,expanded vermiculite, perlite, etc.), fibers, rheopectic agents (e.g.,granular attapulgite, sepiolite, or mixtures thereof), surfactants, andother admixtures as conventionally known in the art.

[0053] Exemplary flowable firestop materials 32 may also compriseintumescent compositions which are known in the fireproofing art. Uponexposure to fire, heat, or flames, such intumescent compositions, astheir name implies, expand considerably in terms of thickness to producean insulative layer of char and char foam.

[0054] Numerous patents and publications have disclosed intumescentcompositions containing one or more polymeric materials in combinationwith phosphate-containing materials and carbonific or carbon-yieldingmaterials, and such compositions, as known in the art, are believed tobe suitable for use as flowable firestop materials 30 of the presentinvention. See e.g., U.S. Pat. Nos. 3,513,114 of Hahn et al.; 5,487,946of McGinniss et al.; 5,591,791 of Deogon; 5,723,515 of Gottfried; WorldPatent No. WO 94/17142 (PCT/US94/00643) of Buckingham; and World PatentNo. WO 98/04639 (PCT/US96/12568) of Janci, all of which are incorporatedfully herein by reference. In U.S. Pat. No. 3,513,114 assigned toMonsanto, Hahn et al. disclosed intumescent compositions comprising anaqueous dispersion of a polyvinyl acetate-containing emulsion, a solventplasticizer, and carbonific ammonium polyphosphates. In U.S. Pat. No.5,723,515 of Gottfried, it was taught to incorporate an elasticity agentsuch as vermiculite, perlite, elastomerics, and acrylics, to increaseresistance of the intumescent coating to cracking and shrinking and toimprove ease of spraying.

[0055] Another intumescent composition, suitable as a flowable firestopmaterial 32 in the present invention, is disclosed in World PatentApplication of Lawrence L. Kuo et al., PCT/US00/18887. This compositioncomprises: a component package for providing a char and char foam; apolymeric binder in emulsion form operative to form a film when thecomposition was allowed to dry; and a crack control agent having a totalof 3 to 6 carbons and a boiling point in the range of 75-175° C., thecrack control agent being represented by the structural formulaR²—O—CH₂—C(R¹)H—O—R³ wherein R¹=—H or —CH₃; and R² and R³ independentlycomprise —H, —R⁴, or —COCH₃, wherein R⁴ comprises a C₁-C₃ alkyl group. Apreferred crack control agent of Kuo et al. comprises alkoxy glycolether, alkoxy glycol acetate, alkoxy glycol ether acetate, or mixturesthereof. An exemplary surfactant package comprises a nonionic alkylarylpolyether alcohol having general formula R—Ø—(OCH₂CH₂)_(x)OH, wherein Ris a C₄-C₈ alkyl group (most preferably, a branched octyl group), Ørepresents a phenylene group, and “x” represents an integer, preferablyin the range of 15-100. Preferred surfactant packages may furthercomprise a dispersant, such as a polyacrylic acid or its salt (e.g.,sodium polyacrylate) or derivatives.

[0056] Other exemplary intumescent materials include graphite flakesimpregnated with sulfuric or nitric acids. Inorganic material flakescapable of exfoliation when heated include vermiculite and perlite.

[0057] Intumscent materials can be used in combination with otherflowable firestop materials 32 in the invention such as Portland cementand/or gypsum containing slurries. For example, in U.S. Pat. No.5,395,571 of Symons, there was disclosed a combination involving gypsumand thermoset resin. Thus, a composition can be made by combining (a) aninorganic base material selected from the group consisting of a calciumsulfate hemi-hydrate, magnesium oxychloride, magnesium oxysulphate and ahydraulic cement; (b) a thermosetting resin which is miscible, solubleor dispersible in water; (c) a suitable amount of a catalyst for thethermosetting resin; (d) water in an amount sufficient to rehydrate theinorganic base material with the water present in the other components;(e) optionally a plasticizer such as a melamine formaldehyde condensate;(f) optionally polyvinyl alcohol; (g) optionally a retarder forretarding the setting time of the inorganic base material; (h)optionally a fibrous reinforcing material; and (i) a foam or a foamingagent. Thus, exemplary flowable firestop materials of the invention maycomprise a hydraulic cementitious slurry containing a portion (e.g.,1-90%) by weight of a polymer, resin, and/or intumescent material, asgenerally known in the art.

[0058] Exemplary flowable fireproofing materials 32 used in theinvention, such as hydratable cementitious slurries, should preferablycontain biocidal agents to combat growth of mold, fungi, and bacteria.These may be supplied in dry powder or liquid form. Materials whichremain wet for long periods of time may be susceptible to mold growth,and thus mold inhibitors should preferably be incorporated into theflowable fireproofing material especially if it is an aqueous mediumsuch as a cementitious slurry. Effective mold inhibition additivesinclude zinc dimethyldithiocarbamate; 1,3benzenedicarbonitrile;2,3,5,6-tetrachlorothiabendazole; 5-chloro-2-methyl-4-isothiazolin-3-oneand 2-methyl-4-isothiazolin-3-one;2,3,5,6-1,3-di(hydroxymethyl)-5,5-dimethylhydantion, ordiiodomethyl-p-tolyl sulfone. More general biocides, such as sodiumhypochlorite or sodium orthophenylphenate tetrahydrate, inhibit bacteriaas well as molds. For some applications, it is important to use abiocide with minimal toxicity to humans.

[0059] Further exemplary flowable firestop materials 32 may comprisesuperabsorbent polymers, either alone or in combination with, forexample, a hydratable cementitious slurry. A superabsorbent polymer isgenerally a cross-linked, hydrophilic polymer that is operative to bindwater and hence to provide a degree of fire or thermal barrierprotection. Examples of superabsorbent materials include hydrolyzedmaleic anhydride polymers and copolymers including copolymers with vinylethers, styrenes, ethylene, and other olefins, polyvinylpyrrolidone,sulfonated polystyrene, polysulfethyl acrylate,poly(2-hydroxyethylacrylate), polyacrylamide, poly(acrylic acid) andalkali metal salts thereof, poly(acrylic acid alkali metal salt), starchmodified polyacrylic acid and alkali metal salts thereof, poly(starchmodified acrylic acid alkali metal salt), hydrolyzed polyacrylonitrileand alkali metal salts thereof, poly(hydrolyzed polyacrylonitrile alkalimetal salt), poly(vinyl alcohol acrylic acid alkali metal salt), saltsthereof and mixtures thereof. Other options for superabsorbent materialinclude poly(acrylic acid alkali metal salt) such as poly(sodiumacrylate), polyhydroxyalkyl acrylates and methacrylates, polyvinyllactams, polyvinyl alcohols, polyoxyalkylenes, natural or syntheticallymodified polysaccharides, proteins, alginates, xanthum gums, guar gums,and cellulosics. Other examples include monovalent and polyvalentinorganic and organic salts of the foregoing polymers comprising acidicor basic functional groups. Alkali metal salts are preferred for acidfunctional polymers.

[0060] Exemplary molding bags 30 of the invention, as previouslymentioned, should be sufficiently flexible to provide for convenience inpositioning the bag, when empty, into opening or gaps of various sizesand shapes, and to provide for expandability in size, upon introductionof the hydratable cementitious material, whereby the molding bagconforms to at least a portion, or the entirety, of the joint gap oropening. Preferably, the bag may be shipped in roll form such that itcan be unrolled into place conveniently during installation.

[0061] The molding bag material should be strong enough to permitfilling by a cementitious slurry under pressure and to retain the slurryuntil it hardens. Since it is the function of the cementitious material,when hardened, to provide a barrier against heat and fire, it is notnecessary for the molding bag material itself to be fire-retardant, andit would be expected for the bag material to be burned or even consumedwhen exposed to fire.

[0062] If the molding bag 30 is made of an air-impermeable material suchas plastic film, paper, waxed paper, or impregnated woven or nonwovenmaterial (e.g., impregnated spunbonded nonwoven polyolefin such asTYVEK® envelope material) the bag should preferably have one or more airevacuation holes 36 or slits to permit air to escape when the bag 30 isfilled with a flowable firestop material 32. The holes should be smallenough, however, so that leakage of flowable firestop material 32 isminimal. The holes should be preferably located on an uppermost face (on30B as shown in FIG. 5 for example) because air will be pushed upwardswithin the molding bag 30 by the pressure of incoming flowable firestopmaterial 32. While it may be possible to roll the molding bag 30 tightlyenough initially to expel the air, the simple act of unrolling the bagis likely to introduce air, thus making it advisable to provide airevacuation holes in the bag. The size of the evacuation holes 36 orslits, as well as their distribution and spacing on the bag, will ofcourse depend on a number of factors, including the nature of thefirestop material injected into the bag, the stretching quality of thebag material, and other factors.

[0063] Exemplary thermal barrier molding bags 30 may be made from a widerange of materials, such as paper, waxed paper, coated paper, cotton,jute, plastic film, felt, woven fabric, nonwoven fabric (e.g.,impregnated spunbonded polyolefin similar to material used in somemailing envelopes), or a combination thereof. Plastic film materials,and in particular thermoplastics such as polyethylene, polypropylene,polyvinyl chloride, polyester, or mixtures thereof, are relativelyinexpensive and would be convenient to use for the applicationscontemplated by the inventors. Preferred bags may be constructed fromcombinations of nylon and polyethylene (e.g., HDPE, LDPE, LLDPE), suchas a polyethylene/nylon/polyethylene layered configuration, which isbelieved to provide a desirable combination of strength with an abilityto form strong heat welded seams. Also, the plastic film material shouldpreferably be completely or partially transparent, to permit installersand inspectors to ascertain visually whether the molding bag has beenfilled adequately with the flowable firestop material 32.

[0064] Other examplary thermal barrier molding bags 30, which aregenerally elongate in shape for insertion into extended joint gaps,preferably have markings or other indicia to serve as indicators forhelping the installer to align placement of the bag within the joint(e.g., the horizontal track 12 on the top of wall). For example, moldingbags 30 can have one or more lines extending longitudinally along thebag, such as on the surface which is intended to serve as the bottom ofthe bag positioned over the horizontal track member 12 of a wall, toserve as guidelines for positioning the bag correctly on top of thewall. Other exemplary bags 30 may have parallel seams or folds or ridgesin the bag that correspond with the edges of the top of the wall (whichis usually about two to six inches in thickness if made of gypsum boardon metal studs, or about eight inches in thickness if made of mortarblocks).

[0065] In further exemplary embodiments, a molding bag 30 can beattached, using adhesive or fasteners, to the horizontal track 12 as aone-piece assembly.

[0066] Exemplary thermal barrier molding bags 30 may have wall (face)thicknesses ranging from 0.1 mils to 60 mils or greater depending uponthe strength of the film or sheet material employed or the number offilms or sheets employed. The molding bags may comprise an elongatedtube shape that is sealed closed at opposing ends by adhesive, heatsealing, stitching, clamping, tying (using string or wire), or othermeans known. The bags may be made by folding over a sheet or film andsealing along peripheral edges to obtain a bag enclosure; or the bag canbe obtained by sealing together two separate sheets or films to form thebag. Exemplary molding bags 20 of the invention may therefore have a“pillow shape” suitable for filling extended longitudinally withinextended joint gaps, such as the “head-of-wall” joint assemblies and“perimeter barrier” assemblies discussed above. Molding bags of theinvention may be made from one layer or two or more layers.

[0067] Exemplary molding bags 30 may comprise plastic films reinforcedwith scrim or mesh, similar to bags which are used for containing meatbones. Such bags are well-known in the food packaging industry and arebelieved to provide increased strength suitable for present purposes.For example, a polypropylene bag can be reinforced with a fiberglassmesh, which decreases the stretchability of the bag.

[0068] As shown in FIG. 7, an exemplary inlet 38 employs a flap 40member that is resiliently biased into a closed position against theopening 39 in the bag material. The flap 40 may, for the purpose ofbeing resiliently biased into a closed position, comprise an elastomeror thermoplastic material, which is partially attached to the innersurface of the bag 30 such as by gluing, hot melt adhesive, sewing, ormelt-sealing. The size and shape of the inlet 38 is preferably chosen tocorrespond with a hose, pipe, or nozzle (not shown) used for conveying aflowable firestop material 32 (e.g., liquid hydratable cementitiousslurry) into the bag 30 (shown by the direction of the arrow “B”). Inthis particular exemplary inlet flap design 28, the pressure of theflowable firestop material 32 in the bag 30 could be used for biasingthe flap 40 into a sealing position (shown by the direction of arrow“C”) against the inner wall of the molding bag 30. Installers would beable to introduce further flowable firestop material 32 into the bagthrough the inlet opening 38, and thus the valve 38/40 is preferablycloseable, and at least one inlet 38 would be positioned along bothlongitudinal edges of the molding bag 30, so that when the bag 30 ispositioned in correct alignment on top of a vertical wall with bothlongitudinal edges hanging down on either side of the wall, the inletopenings 38 are conveniently accessible to workers from either side ofthe wall. In still further exemplary embodiments, the inlet valves 38can be located towards the center along one or both longitudinallyextending edges of the molding bag 30 to minimize the travel distance offlowable firestop material 32 to be introduced into the bag and toincrease the likelihood of filling the molding space within the bag asmuch as possible without leaving air spaces in the hole or joint inwhich the bag is positioned.

[0069] In another exemplary inlet, a screw cap assembly may be employedin a manner similar to the plastic caps on gable-topped orange juice andmilk cartons (e.g., waxed cardboard type). It is also possible to employscrew cap assemblies having a directional valve (e.g., rubber flap asshown in FIG. 7). Still further exemplary valves may include ball valveswherein a ball is rotated between a closed position and open positionwhereby inlet and outlet are connected by a channel running through theball. Other exemplary valves may include a globe style valve, in which aseal moves to press against a “volcano” style orifice. Further exemplaryvalves may include check valves, wherein a flap or other occlusionmember seated on a base over the inlet orifice may be moved to an openvalve position when the flowable firestop material 30 is introduced intothe molding bag, and is then moved into a closed valve position by abiasing means, such as a spring, hinge, or connecting member whichconnects the flap or occlusion member to the base.

[0070] As shown in FIG. 8, exemplary inlet valves may be incorporated aspart of the seamed edges 31 of bags 30 (i.e., the seam 31 otherwisejoins faces 30A and 30B) in the form of tubes or sleeves 42 which areoperative to convey flowable firestop material into the bag 30 (the flowdirection of which is indicated by the arrow “D”) and also operative tobecome sealed in a closed position by the pressure of the flowablefirestop material within the bag (the pressure exerted by the flowablematerial 32 to close the valve is indicated by the arrows designated“E”). The tube or sleeve 42 may be connected into the bag 30 at the seamusing an adhesive, melt-sealing, or other means known; and may extendfor any desirable length outside and beyond the molding bag 30. Usinglong tubes 42 may provide convenience in high head-of-wall jointassemblies located seven feet or more above floor level, because itwould be possible, such as by using extended tubes or sleeves 42 whichdangle from bags positioned on the top of the wall, to introduceflowable firestop material 32 into the molding bags without having toascend a ladder. After filling, the tube or sleeve 42 can be tied orpinched off, reopened, and re-closed using string, rubber band, clip, orother convenient means, below the top of the wall.

[0071] As shown in FIG. 9, an exemplary thermal barrier 1 of theinvention can be used to fill one or more gaps or cavities in the“head-of-wall” joint defined between a fluted metal ceiling 10 and ametal stud assembly. The molding bag is positioned between thehorizontal track 12 before the track 12 is fastened to the bottomsurfaces 10B of the ceiling 10 (e.g., using screws or other fasteners).The metal studs 14 are then installed between the track 12 and floor(not shown), and one or more gypsum wallboards 18 are attached to one orboth sides of the track/stud assembly (12/14/18). Preferably, a spacerstrip 21 (e.g., mineral wool or foamed polystyrene or other compressiblematerial) is inserted to protect the gap at the top of the wallboards18. A flowable firestop material is then introduced into the bag 30through an inlet 38, preferably located along a longitudinal edge of thebag 30. Preferably, the bag has a series of pleats 34 allowing the bagto expand when filled with the flowable firestop material. The flowablefirestop material, under force of pressure, should travel along thelongitudinal edges of the bag (designated at 33) which overhang oneither side of the wall assembly (12/14/18), and should preferably fillthe joint cavities between the top of the wall (12) and uppermostceiling surface 10A as well as to fill the bag over the corner joints 20above the wallboards 18.

[0072] As shown in FIG. 10, an exemplary thermal barrier molding bag 30and method of the invention may be used to install a thermal barrier ina so-called “perimeter assembly” in the joint between a vertical wall 44and floor 46. In this situation, it is preferable to use a spacer 21which could be a plastic bag filled with air or a wad or stack ofmineral wool, preferably wrapped in a sleeve or envelope, or otherresiliently compressible object. The spacer 21 may be adhered orotherwise fastened to the floor 46 using known means. The molding bag 30may be attached to the wall 44 such as by using nails or screws alongthe top edge or seam 31 of the bag, using a screw, nail, tack, oradhesive (such as used in structural waterproofing), or other knownmeans. Preferably, the molding bag 30 has one or more inlets 38, such asscrew caps, located towards the top of the bag. The inlets 38 may beused also for the purpose of evacuating residual air in the bag duringthe process of filling it with a flowable fireproofing material 32.Preferably, a portion of the bag extends across the gap between floor 46and wall 44 and rests on a portion of the floor 46 without beingattached or fixed to the floor so as not to impede movement of the flooror wall.

[0073] In further exemplary embodiments of the invention, a thermalbarrier molding bag may comprise two or more compartments or,alternatively, comprise two or more bags connected to each other topermit flowable firestop material to be introduced into one bag (orcompartment) to flow into a second bag (or compartment). As shown inFIG. 11, an exemplary thermal barrier bag 1 may be comprised of aplurality of bags or compartments extending longitudinally in theperimeter joint between floor and wall (or turned sideways, this couldbe an illustration of a ceiling and wall). Bag enclosures are connectedto each other by a plurality of connecting holes or conduits asdesignated at 48. For example, plastic tube-like bags could be connectedto each other periodically along their length, such as by the use ofmelt-sealing or grommets, at holes 48 to permit flowable firestopmaterial to flow from one bag enclosure to another. The bag device 20 ispreferably attached to the wall 44 adhesively or by mechanicalfasteners.

[0074] Exemplary thermal barrier molding bags 30 of the invention mayoptionally have a pressure sensitive adhesive layer, grommets, or othermeans for allowing the bag to be adhered or mechanically attached to awall, ceiling, floor, or other building or vessel structure. Forexample, the bottom side 30B of the bag 30 shown in FIG. 5 can besupplied with a two-sided tape, covered by a releasable sheet, to permitthe bag device 30 to be adhered to the horizontal track 12 before it isfastened to or disposed against the ceiling, as illustrated in FIGS. 3and 4.

[0075] In addition to being useful for creating barriers in“head-of-wall” joints and “perimeter barrier” joints, the thermalbarriers and methods of the invention may be used with good advantage inprotecting “penetration” openings, such as “annular” spaces in whichcables, ducts, pipes, wires, or electrical panels are situated. Anexemplary method of the invention comprises providing an opening in abuilding structure (e.g., wall, floor, or ceiling) having a cable, duct,pipe, wire, or electrical panel in said opening and defining an annularor otherwise partially occluded space within said opening; insertinginto said space a thermal barrier molding bag; and introducing into saidmolding bag a flowable firestop material, such as described above.Consequently, the bag inflates and forms a seal within the opening toprovide a barrier to both sides of the wall, ceiling, or floor opening.In cases wherein the conduit or electrical panel is not physically incontact with the surrounding wall, ceiling, or floor, then the space inthe opening surrounding the conduit or electrical panel is completelyannular (i.e., it surrounds the conduit), and this annular space can befilled, for example, by wrapping a molding bag at least once around theconduit. If the conduit is a plastic pipe or plastic covered wire orcable, it is preferable to use an intumescent material in the moldingbag or outside of the bag but surrounding the conduit, such that if theconduit (e.g., plastic pipe, cable jacket) melts during the fire, thenthe intumscent material can expand under the effect of heat to fill thespace left by the melted plastic.

[0076] When installed in the hole or joint gap of a building structure,the in-situ molded thermal barriers of the invention are tightlyconformed to the shape of the structure or structuressurrounding/defining the hole or joint gap. It is envisioned thatpreferred thermal barriers of the invention, when installed in jointassemblies, are capable of passing fire endurance tests and hose streamtests in accordance with the “UL Standard for Safety for Tests for FireResistance of Building Joint Systems, UL 2079,” Third Edition, DatedJul. 31, 1988, (Underwriters Laboratories, Inc., Northbrook, Ill.),incorporated fully herein by reference. Fire endurance testing pursuantto UL2079 involves exposing a sample portion of a joint assembly in atest furnace. More accurately speaking, the joint assembly is sealedagainst the furnace with an insulating gasket between the joint assemblyand the furnace (UL 2079). The representative joint assembly can be, forexample, a thermal barrier installed in a head-of-wall joint having oneor more gypsum boards on either side of metal studs to simulate a wall(typically 2.5-8 inches or more in total thickness) and fluted metalplate to simulate a ceiling deck (as described above). One side of thethermal barrier in the joint would be exposed to heat of the furnace inaccordance with a standard time-temperature curve (ASTM E119). Thistime-temperature curve has characteristic points, as follows:

[0077] 50-90 degrees F. (10-32 degrees C.) at 0 minutes

[0078] 1000 degrees F. (538 degrees C.) at 5 minutes

[0079] 1300 degrees F. (704 degrees C.) at 10 minutes

[0080] 1550 degrees F. (843 degrees C.) at 30 minutes

[0081] 1700 degrees F. (927 degrees C.) at 1 hour

[0082] 1850 degrees F. (1010 degrees C.) at 2 hours

[0083] One or more thermocouples are installed against the thermalbarrier on its “cool” side (i.e., unexposed side of joint opposite tothat which is exposed to furnace), and the temperature of thethermocouple is monitored. The test is then conducted until failure isobserved. Failure can be detected by holding a cotton waste pad (100 by100 by 19 mm) directly over the observed crack or hole in the jointsystem, approximately 25 mm from the breached surface, for a period of30 seconds. If the cotton ignites (glows or flames) within this period,then integrity failure has been reached. In the alternative, failure issaid to be attained when the temperature of the thermocouple has risenby at least 325 degrees Fahrenheit above the starting temperature.Accordingly, exemplary thermal barriers of the present invention (madein situ, or, in other words, in the joint gap) have the ability toresist failure, for a minimum period of at least 60 minutes, andpreferably for at least 120 minutes, when tested pursuant to theabove-summarized fire endurance test in accordance with UL 2079.

[0084] Other preferred exemplary thermal barriers of the inventionshould have the ability to maintain barrier integrity when subjected tothe hose stream test, which is also described in UL 2079. For example, ahead-of-wall joint system is subjected to the above-described fireendurance test for a period of time not more than sixty (60) minutes,and then within ten (10) minutes thereafter the joint assembly issubjected to a stream of water delivered through a 2.5 inch (64 mm) hoseand discharged through a National Standard playpipe of correspondingsize equipped with a 1 ⅛ inch (29 mm) discharge tip of thestandard-taper, smooth-bore pattern without a shoulder at the orifice.The water pressure and duration of the application is to be specified inthe table below: TABLE 1 (Pressure and Duration of Hose Stream Test)Water pressure at Duration of application, Hourly fire rating base ofnozzle, seconds per square foot time, minutes Psi (kPa) (s/m²) ofexposed area^(a) 240 • time < 480 45 (310) 3.0  (32) 120 • time < 240 30(210) 1.5  (16)  90 • time < 120 30 (210) 0.90 (9.7)     time < 90 30(210) 0.60 (6.5)

[0085] Accordingly, preferred thermal barriers of the invention (made inthe joint gap), subsequent to application of the aforementioned fireendurance test, should be able to pass the hose stream test, inaccordance with UL 2079. In other words, the thermal barriers shoulddemonstrate the ability to resist dislodgement from the joint gap bywater pressure from a hose, for a given period of time, as indicatedabove in the chart with respect to the applicable hourly fire ratingtime. The nozzle orifice is to be 20 feet (6.1 m) from the center of theexposed surface of the joint system if the nozzle is so located that,when directed at the center, its axis is normal to the surface of thejoint system. If the nozzle is unable to be so located, it shall be on aline deviating not more than 30 degrees from the line normal to thecenter of the joint system. When so located its distance from the centerof the joint system is to be less than 20 feet (6.1 m) by an amountequal to 1 foot (305 mm) for each 30 degrees of deviation from thenormal (UL 2079).

[0086] FIGS. 12-14 are cross-sectional plan views of further exemplarymolding bag barrier assemblies, installed at the top of a wall, andlocated under a fluted metal ceiling (not shown).

[0087] As illustrated in FIG. 12, the molding bag 30 may be positionedover or adhered to a platform strip 50 which is operative to support thebag 30 such that, when filled, the bag 30 extends over and above thegypsum wall boards 18 and allows space for them to expand upwardstowards the bag 30 (due to thermal cycling). The platform strip 50 maybe constructed of any rigid material, such as for example a corrugatedplastic sheet, preferably one in having corrugations alignedperpendicularly with respect to the length of the bag. Accordingly, afurther exemplary method of the invention comprises attaching alongitudinal platform strip 30 to a horizontal track, before attachingthe track to a ceiling. The platform strip 30 may have an adhesive layeron one or both sides to permit attachment of the bag 30 and/orhorizontal track member 12, as well as to maintain their properpositioning relative to each other and to the track 12, duringinstallation.

[0088]FIG. 12 also illustrates the use of sealing ribbons 52 to ensure abarrier seal between the lower portions 30 (or “ears”) of the moldingbag 30 and the gypsum boards 18. These sealing ribbons 52 may be made oftapes, having a strip material and adhesive layer, to permit the ribbons52 to adhere intimately with the lower portions 33 of the bag 30 and thegypsum boards 18. These ribbons 52 prevent heat and smoke frompenetrating through spaces between the boards 18, horizontal trackmember 12, platform strip 50, and/or molding bag 30. The ribbons 52 maybe constructed from the same kind of materials used for making the bag30 as described above. Adhesives used for attaching the ribbons 52 tothe bag 30 and gypsum boards 18 are preferably chosen to resistdegradation at high temperatures (e.g., which become tacky but do notdegrade between 200-425° F. If the ribbons 52 are attached to theoutward facing portion of the bag 30 (i.e., on a bag surface that facesaway from the gypsum board face), then preferably a fold or extramaterial should preferably be used between the respective points ofattachment on the bag 30 and gypsum board 18 to accommodate cyclingmovement (of the wall and gypsum boards 18). This is probably notnecessary in situations wherein the ribbons 52 are installed on asurface of the lower bag portions 33 immediately facing against thegypsum board 18. Alternatively, one can spray an elastomeric materialbetween the lower bag portions 33 and gypsum boards 18 to achieve asimilar sealing purpose.

[0089] Accordingly, further exemplary methods of the invention comprisecreating a barrier in a hole or joint cavity, as above-described, andfurther comprising attaching a ribbon to the bag and to at least onebuilding structure, such as the wall (gypsum board) adjacent to saidbag, so as to provide a further barrier to penetration by fire and/orsmoke.

[0090] In a still further embodiment, illustrated in FIG. 13, a linersheet 54 may be placed between the bag 30 and platform strip 50 (e.g.,on top of the strip 50), and allowed to drape downwards whereby opposedliner sheet edges 54A and 54B reside between the horizontal track 12 andgypsum boards 18. The liner sheet 54 functions to provide an additionalprotection to penetration by heat or smoke at the top of the wall.Alternatively, as shown in FIG. 14, a liner sheet 54 may be placedbetween the horizontal track 12 and platform strip 50 to achieve thesame purpose, and would be suited for situations wherein the platformstrip 50 is pre-attached to the bag 30. It is contemplated that infurther embodiments, the molding bag 30, platform strip 50, and linersheet 54 may be attached to each other prior to being juxtaposed againstor attached to the horizontal track 12.

[0091] The liner sheet 54, as well as platform strip 50, may be made ofthe same material as the molding bag 30. In further exemplaryembodiments, all of these (sheet 54, strip 50, and bag 30) may also beconstructed from carbon fiber, refractory ceramic fiber, fiber glass,calcium silica fiber, mineral wool, foil-covered fiberglass sheets,paper/fiberglass sheets, or similar materials, preferably of a hightemperature resistant nature.

[0092] The present invention also provides a barrier assembly, examplesof which are illustrated in FIGS. 13 and 14. Such an exemplary barrierassembly would comprise at least one barrier molding bag 30 and at leastone liner sheet 54 and/or at least one support strip 50. In furtherexemplary barrier assemblies, the liner sheet 54 can be pre-attachedbetween and to the bag 30 and support strip 50, as shown in FIG. 13; or,more preferably, the support strip 50 can be pre-attached between thebag 30 and support strip 50, as shown in FIG. 14. An optional adhesivelayer (not shown) can be pre-attached to the support strip 50 and/orliner sheet 54 to facilitate fabrication or installation of theexemplary barrier assemblies illustrated in FIGS. 13 and 14.

[0093] If a liner sheet 54 is used (e.g., FIGS. 13 and 14), it ispossible that the molding bag 30 can be used without the requiring thedownward hanging flaps 33 (or “dog-ears”) to protect the joint at thetop of the drywall boards 18 where they meet the horizontal track 12.However, if the flaps or downward projections 33 are not employed, itwould be preferable to pack mineral wool or other protective material inthe small gap on top of the drywall boards 18 to provide furtherprotection against head and fire (and also to permit cycling of theboards 18).

[0094] A still further exemplary molding bag of the invention is shownin the cross-sectional (transverse) view illustrated in FIG. 15. Themolding bag 30 is constructed using a top sheet 30A which is preferablyformed by sewing, adhering, melt-bonding, or otherwise attaching anelastic strip material 35 in a stretched mode to the sheet 30A, toprovide folds, pleats, or crinkles (to permit expansion of the bag 30when flowable firestop material is introduced); and a bottom sheet 30B.The top 30A and bottom 30B sheets may be adhered together at edge seamsusing adhesive, sewing, melt-bonding, or other means known.

[0095] As seen in FIG. 15, an internal expansion restraint structure 31is used to control the shape of the bag 30 when flowable firestopmaterial is introduced into the bag. As more clearly seen in theperspective partial view illustrated in FIG. 16, an exemplary internalexpansion restraint structure 31 may comprise a strip or “ribbon” ofmaterial having longitudinally extending opposed parallel edges that areadhered, welded, sewn, or otherwise attached to the bottom sheet 30Bmaterial. The internal expansion restraint structure 31 facilitates theshaping, when flowable firestop material is introduced into the bag, ofthe downward hanging flaps 33 or “dog-ears” used for protecting thehorizontal track in a head-or-wall joint assembly. Valve 38 is shown atthe bottom of the flaps 33 to permit flowable firestop material to beintroduced into the bag 30. The internal expansion restraint structure31 should preferably have performations, or, as more clearly shown inFIG. 16, large openings 31B (e.g., 1-3 cm) to permit the firestopmaterial to flow from the flap portions 33 into the rest of the moldingbag 30.

[0096] In further exemplary embodiments, the size of the portions of theinternal expansion restraint structure 31 residing between the openings31B may be selected so that they tear or rupture when a certain pressure(caused by introducing flowable firestop material into the bag 30) isreached. In other words, the portion of the internal expansion restraintstructure 31 which resides between the openings 31B and the seamed orattached portions where the structure 31 contacts the bottom sheet 30Bcan be selected, in terms of size or thickness wall, to break or pullapart a predetermined pressure is reached inside the bag. Thus, forexample, further exemplary bags and methods of the invention involveproviding a bag structure that audibly and/or visually indicates (suchas bursting of part of the wall of the internal expansion restraintstructure 31) when the bag has been sufficiently filled. In cases wherethe internal expansion restraint structure 31 is made of plastic, themolding bag can provide both a visual and audible indication when highpressure is reached (meaning that the bag is sufficiently full) becausea portion of the internal expansion restraint structure 31 will emit aloud “popping” or bursting sound, and the bag will consequently have abulge at the place where the internal expansion restraint structure 31has ruptured or broken.

[0097] In further exemplary embodiments, the top 30A and bottom 30Bsheet portions of the molding bags, at an end of the bag, may not bedirectly seamed together at the bag end, but are instead seamed to anoptional end-wall portion having one or more folds or pleats to permitthe bag to expand in volume at the end of the bag. This feature ishelpful when the end of the bag is located in a fluted metal deck cavity(ie. the cavity formed between the top ceiling portion and top of thewall), and especially so when the bag abuts the end of another bag inthe cavity. Thus, an exemplary molding barrier bag of the inventioncomprises a first major sheet attached to a second major sheet, saidbarrier bag having at least one end at which said first and second majorsheets are each attached to an end wall having at least one pleat orplurality of crinkles to permit expansion of said molding barrier bag atsaid at least one end.

[0098]FIG. 17 is a cross-sectional view of an exemplary method andbarrier assembly, wherein a molding bag 30 is positioned in a “U” shapedtrack 13 which is then positioned against a fluted metal ceiling. The“U” shape confines expansion of the bag 30 against the top surface 10Aof the fluted metal ceiling (16); allows firestop material 32 to flowbeneath the bottom surface 10B of the ceiling; and prevents interferencebetween bag 30 and wall boards 18. The “U” shaped track 13 and track 14together form an “H” shape.

[0099] The foregoing discussion and examples are provided forillustrative purposes and not intended to limit the scope of theinvention as claimed.

We claim:
 1. A method for installing a barrier, comprising: providing afirst structure having a hole, or providing a first structure and asecond structure defining therebetween a gap; introducing into said holeor gap at least one barrier molding bag that is operative to receive andsubstantially to contain a flowable firestop material; and introducing,into said at least one barrier molding bag, a flowable firestopmaterial, thereby creating a barrier in said hole or gap.
 2. The methodof claim 1 wherein said first structure is a vertical wall.
 3. Themethod of claim 2 wherein said vertical wall comprises gypsum boardsupported by framework.
 4. The method of claim 1 wherein said firststructure is a wall and said second structure is a floor.
 5. The methodof claim 4 said vertical wall comprises gypsum board supported byframework, and said ceiling comprises fluted metal.
 6. The method ofclaim 4 wherein said second structure is a floor.
 7. The method of claim1 wherein said first and second structures are walls definingtherebetween a gap.
 8. The method of claim 1 wherein said flowablefirestop material comprises a hydratable cementitious slurry comprisingPortland cement, gypsum, or mixture thereof.
 9. The method of claim 8wherein said hydratable cementitious slurry, and said slurry containsPortland cement.
 10. The method of claim 8 wherein said flowablefirestop material further comprises at least one admixture selected fromset accelerators, set retarders, water reducers, superplasticizers,fluidity enhancing agents, rheology modifiers, air entraining agents,pigments or colorants, aggregates, fibers, rheopectic agents,surfactants, antibacterial agents, or mixture thereof.
 11. The method ofclaim 8 wherein said hydratable cementitious slurry further comprises anair entraining agent and a water reducing agent.
 12. The method of claim1 wherein said flowable firestop material comprises an intumescentmaterial.
 13. The method of claim 1 wherein said flowable firestopmaterial comprises a superabsorbent polymer, a desiccant, hydratedsilica gel, or mixture thereof.
 14. The method of claim 1 wherein saidbarrier molding bag is constructed from paper, waxed paper, coatedpaper, cotton, jute, plastic film, felt, woven fabric, nonwoven fabric,or a mixture thereof.
 15. The method of claim 14 wherein said barriermolding bag is constructed essentially from plastic film.
 16. The methodof claim 15 wherein plastic is selected from polyethylene,polypropylene, polyvinyl chloride, and a mixture thereof.
 17. The methodof claim 15 wherein said plastic film is substantially transparent. 18.The method of claim 15 wherein said barrier molding bag is constructedof a first plastic film and a second plastic film heat-sealed togetherto form said bag.
 19. The method of claim 1 wherein at least one of saidplastic films comprises at least one folded pleat.
 20. The method ofclaim 1 wherein said at least one barrier molding bag comprises a seriesof pleats or a plurality of crinkles.
 21. The method of claim 1 or 15wherein said barrier molding bag has a generally elongated body havingopposed longitudinally extending first and second edges, said moldingbag further having a plurality of holes along said elongated body tofacilitate evacuation of air when a flowable firestop material isintroduced into said molding bag.
 22. The method of claim 21 whereinsaid barrier molding bag has at least one inlet located along at leastone of said edges for permitting flowable fireproofing material to beintroduced into said bag.
 23. The method of claim 22 wherein saidbarrier molding bag has at least one inlet located along each of saidfirst and second longitudinally extending edges.
 24. The method of claim23, for installing a barrier in a head of wall joint, wherein saidbarrier molding bag has inlet flap members for allowing flowablefirestop material to flow into said molding bag.
 25. The method of claim1 wherein said barrier molding bag has at least two compartmentsconnected to each other to permit flowable fireproofing materialintroduced into a first of said compartments to flow into the second ofsaid compartments.
 26. The method of claim 1 wherein said firstintroducing step comprises introducing a first barrier molding bagconnected to a second barrier molding bag, whereby flowable firestopmaterial introduced into a first of said molding bags flows into theconnected molding bag.
 27. The method of claim 1 wherein said barriermolding bag is inserted into a hole of a structure, said structure holehaving pipe, duct, cable, wire, or electrical panel located therein. 28.The method of claim 1 wherein said flowable firestop material is allowedto harden.
 29. A barrier comprising a bag having firestop material madein accordance with the method of claim
 1. 30. The barrier of claim 29wherein said molding bag contains hardened firestop material having afire endurance, when tested in accordance with UL 2079, of at least 60minutes.
 31. The barrier of claim 29, wherein said molding bagcontaining hardened firestop material is capable of avoiding failurewhen subjected to a hose stream test in accordance with UL 2079 in atleast one of the hourly fire rating times indicated below: Duration ofapplication, Water pressure at seconds per square foot Hourly firerating base of nozzle, (s/m²) of exposed time, minutes Psi (kPa)area^(a) 240 • time < 480 45 (310) 3.0  (32) 120 • time < 240 30 (210)1.5  (16)  90 • time < 120 30 (210) 0.90 (9.7)    time < 90 30 (210)0.60 (6.5)


32. The barrier of claim 30 wherein said molding bag contains hardenedfirestop material having a fire endurance, when tested in accordancewith UL 2079, of at least 120 minutes.
 33. A joint assembly comprisingat least two adjoining structures defining therebetween a gap, said gapcontaining a barrier made in accordance with the method of claim
 1. 34.A firestop molding bag, comprising: a first face, a second face, saidfirst and second faces being connected to each other around peripheraledges thereby defining a bag enclosure for receiving a flowablefireproofing material, at least one of said first and second faceshaving a plurality of holes operative to release air pressure when saidbag enclosure is filled with a flowable fireproofing material; said baghaving a generally elongate body defined by a length dimension thatexceeds a width dimension, at least one of said first and second faceshaving pleats or crinkles oriented perpendicularly with respect to saidlength dimension, said pleats or crinkles operative to permit expansionof the bag when flowable fireproofing material is introduced.
 35. Thebarrier molding bag of claim 34 wherein at least one of said first andsecond faces comprises a transparent plastic film, said bag furtherhaving at least one inlet for introducing into said bag a flowablefireproofing material.
 36. The barrier molding bag of claim 34 whereinsaid bag has two opposed ends defining therebetween an elongated body,said elongated body having opposed longitudinally extending seams, andat least one inlet located along each of said opposed longitudinallyextending seams to permit a flowable fireproofing material to beintroduced into said bag.
 37. The barrier molding bag of claim 34wherein said pleats or crinkles are attached to an elastic band.
 38. Thebarrier molding bag of claim 34 further wherein said bag is attached toa support strip extending along said elongated body.
 39. The method ofclaim 5 further comprising providing a support strip to support saidmolding bag when positioned over the top of a wall.
 40. The method ofclaim 1 further comprising attaching a ribbon element to the bag and toat least one building structure adjacent to said bag, so as to provide afurther barrier to penetration by fire and/or smoke.
 41. The method ofclaim 20, wherein said pleats or crinkles are formed by attaching anelastic material, while said elastic is in stretch mode, to a sheetcomponent of said molding bag.
 42. The barrier molding bag of claim 34having at least one end at which said faces are each attached to an endwall having at least one pleat or plurality of crinkles to permitexpansion of said bag at said at least one end.
 43. An exemplary barrierassembly, comprising a bag having an inlet for receiving a flowablefirestop material, a support strip for supporting the bag when installedin a head of wall joint, and a liner sheet.
 44. The barrier assembly ofclaim 43 wherein said bag, support strip, and liner sheet are attachedtogether as an integral unit.
 45. The barrier assembly of claim 44wherein said support strip is attached between said bag and liner sheet.46. The method of claim 1 wherein said bag is inserted into a “U” shapedtrack and affixed to a fluted metal ceiling.